1. Field of the Invention
The present invention relates to an electronic mail-capable communication terminal device like a facsimile machine provided with the ability to access electronic mail.
2. Description of the Related Art
In recent years, computer communication networks like the Internet, comprised of local computer communication networks further networked over communications lines and capable of transmitting electronic mail, have grown. Computer communication networks allow for easy error correction, and permit communication with computers not only domestically, but from overseas, as well, at only the cost of communicating with a local provider (a service that provides connection to a computer network.)
Conventional communication procedures and methods for Group 3 ("G3", International Telecommunications Union (ITU)-T recommendation T.4) facsimile machines differ from that of computer communication networks, and therefore it is not possible to connect these machines directly to computer communication networks. However, by converting into electronic mail format the image data of a document to be sent, facsimile machines can be enabled to transmit image data to these computer communication networks.
When a facsimile machine provided with electronic mail communication capabilities transmits electronic mail via the Internet, the facsimile machine dials the telephone number of the Internet Service Provider ("ISP"), logs-in by entering the user name and password of the registered user, and then sends a electronic mail. The host computer of the provider locates and sends the mail to an optimal gateway on the Internet in order to transmit the mail to the mail address of the recipient. The electronic mail message is passed from gateway to gateway along the Internet, and finally to the server in which the recipient's mailbox is located. The mail is then stored in the mailbox at the recipient's electronic mail address.
The recipient accesses the network, checks his or her mailbox, and if retrievable mail is found, downloads the mail from the mailbox.
As described above, the mail sender must first access the network provider in order to send the mail. However, during certain periods there may be heavy traffic on the ISP's phone lines, and this may prevent a user from being able to dial-in to its provider. Further, if the user name or password input during log-in is incorrect, the log-in will fail. Still further, if the recipient's mail box is overloaded, the mail box (mail server) may reject any new incoming messages.
Further, when the sender checks its mailbox and discovers the presence of mail that has been returned from the network because the recipient is unknown ("returned mail"), the original document must be rescaned in order to be resent. The presence of the returned mail is known by finding the character code of the Subject field (which carries subject information of the mail such as title of the mail) in the data that follows the mail header and finding a particular code which specifies the sender itself in the character code.